97 Mark VIII Stalling and I have no idea why?!?!?

[mark0101]

I have 97 Mark VIII with 144k on it. The car keeps stalling and shutting off while I am driving. Sometimes it stalls when am coming to a stop. Here is a video of what its doing.

I have replaced the fuel filter, checked fuel pressures (which were good even when it stalled), changed my MAF, IAC, and changed my PCM. NOTHING has helped, the car is not giving any codes at all. I am at ends with this right now.

It will stall and I will try to crank it and it wont start. I will wait 10 mins or so and car starts right back up.

WTH can this be. Oh yeah, Battery (no corrosion) and alternator are fine also.

 

[Ford nut]

could be crank sensor check for spark when car is in a no start condition, no spark would make me replace the crank sensor.

 

[tixer]

Good call. And check the wiring harness for it. It's underneath, near the AC compressor. Often the connector can be fouled by oil leaks.. which is handy, because the sensor is a bit tough to extract.

 

[driller]

That's not what I would call "stalling", that is more like "shutting off".

So, I tend to agree it could be the crank sensor or harness since it controls the ignition.

 

[chris2523]

classic crank sensor.

 

[mark0101]

Gonna replace the crank sensor tonight. Will update afterwards. So it did finally through a code P0320, so really hoping its just this.

 

[mark0101]

Ok, so after replacing the Crank sensor, it hasn't just "shut down" so far. But it's still stalling when coming to a stop or making a left turn. Now it was doing this when the car was "shutting down" also but I didn't put that in my first post.

Now Both of these problems started at the same time. It looks like a case of a bad IAC. I used to have another 97 Mark VIII (now a parts car) which I had replaced the IAC with an advance auto parts one. That Mark used to work fine with it and that's the IAC I have put on this problematic Mark VIII. I will get a motorcraft IAC but can you guys think of anything else. No cracked hoses or vacuum leaks I can hear.

 

[Ford nut]

Check for a miss, COP's free of oil?

 

[KStromberg]

Just for the hell of it, check your TPS voltage with an ohm meter and be sure your resistance values are on point from closed to full open.

 

[mag]

Dies out turning or coming to a stop HMMM .Does this happen with a full tank fuel

 

[tixer]

Do follow the wiring harness back to the main loom from that crank position sensor. Mine had been crushed between the front sway bar and the bottom of the AC compressor, causing a similar condition.

 

[mark0101]

The wiring looks good. Replaced the TPS from my parts Mark VIII and its been running fine for the past five days now with no previous symptoms so far.